Persistence via PowerShell profile

Elastic Stack Serverless Security

Identifies the creation or modification of a PowerShell profile. PowerShell profile is a script that is executed when PowerShell starts to customize the user environment, which can be abused by attackers to persist in a environment where PowerShell is common.

Rule type: eql

Rule indices:

• winlogbeat-*
• logs-endpoint.events.*
• logs-windows.*

Severity: medium

Risk score: 47

Runs every: 5m

Searches indices from: now-9m (https://www.elastic.co/guide/en/elasticsearch/reference/current/common-options.html#date-math[Date Math format], see also Additional look-back time)

Maximum alerts per execution: 100

References:

• https://learn.microsoft.com/en-us/powershell/module/microsoft.powershell.core/about/about_profiles
• https://www.welivesecurity.com/2019/05/29/turla-powershell-usage/

Tags:

• Elastic
• Host
• Windows
• Threat Detection
• Persistence

Version: 1

Rule authors:

• Elastic

Rule license: Elastic License v2

file where event.type != "deletion" and
  file.path : ("?:\\Users\\*\\Documents\\WindowsPowerShell\\*",
               "?:\\Users\\*\\Documents\\PowerShell\\*",
               "?:\\Windows\\System32\\WindowsPowerShell\\*") and
  file.name : ("profile.ps1", "Microsoft.Powershell_profile.ps1")

Framework: MITRE ATT&CKTM

• Tactic:

  • Name: Persistence
  • ID: TA0003
  • Reference URL: https://attack.mitre.org/tactics/TA0003/

• Technique:

  • Name: Event Triggered Execution
  • ID: T1546
  • Reference URL: https://attack.mitre.org/techniques/T1546/

• Sub-technique:

  • Name: PowerShell Profile
  • ID: T1546.013
  • Reference URL: https://attack.mitre.org/techniques/T1546/013/